Apparatus for turning heavy loads such as stone

ABSTRACT

Load turning sling means for handling heavy loads such as stone slabs and the like, and comprising a frame having brackets suspended therefrom for supporting a drive shaft in journaled relationship therewith. Drums are secured to opposite ends of the drive shaft, with the drums having an outer sling receiving drive surface thereon and a sling retaining head at each end of each drum. A pair of endless loop slings are arranged in captive relationship over the drums, and free to be positioned thereover, thus providing the load turning sling for handling loads suspended therefrom. The slings preferably have a high friction surface for frictionally engaging the sling receiving drive surface of the drum.

llit its Schlough APPARATUS FOR TURNING HEAVY LOADS SUCH AS STONE [75]Inventor: Thomas L. Schlough, St. Cloud,

Minn.

[73] Assignee: The Gran-A-Stone Co., Park Tool Company Division, St.Cloud, Minn.

221 Filed: Apr. 28, 1972 21 Appl. No; 248,675

[52] US. Cl. 294/74, 294/67 R [51] Int. Cl. B66c 1/18 [58] Field ofSearch 294/67 R, 67 B, 67 BA,

294/67 DA, 67 E, 67 EA, 74, 81 R; 214/338, 339, 340; 254/184; 212/128;29/282 1 May 7,1974

Assistant Examiner-Johnny D. Cherry [57] ABSTRACT Load turning slingmeans for handling heavy loads such as stone slabs and the like, andcomprising a frame having brackets suspended therefrom for supporting adrive shaft in journaled relationship therewith. Drums are secured toopposite ends of the drive shaft, with the drums having an outer slingreceiving drive surface thereon and a sling retaining head at each endof each drum. A pair of endless loop slings are arranged in captiverelationship over the drums, and free to be positioned thereover, thusproviding the load turning sling for handling loads suspended therefrom.The slings preferably have a high friction surface for frictionallyengaging the sling receiving drive surface of the drum.

7 Claims, 2 Drawing Figures APPARATUS FOR TURNING HEAVY LOADS SUCH ASSTONE BACKGROUND OF THE INVENTION The present invention relates to animproved load supporting or slab turning device particularly arranged tohandle heavy objects such as stone slabs and the like. Morespecifically, the apparatus of the present invention provides animproved means for handling heavy loads with a pair of axially spacedslings, with the slings being adjustably arranged to be positioned toform a cradle or the like to support and otherwise transfer the loadfrom one disposition to another. One particular advantage of theapparatus is its ability to handle somewhat irregularly shaped loads,such as stone slabs or the like which have not been completely out orotherwise treated so as to assume a rectangular parallelepipedonconfiguration.

In the past, various sling devices have been utilized to form cradles orthe like for supporting heavy loads, however these devices havegenerally been adapted for use with regularly shaped stone or otherlarge objects, and difficulty has frequently been encountered inarranging a structure to handle loads which do not have a regularconfiguration. For example, when irregularly shaped loads are beinghandled and turned or otherwise rotated, any irregularity in theconfiguration will frequently result in a crawling of the sling on thesupport. If the crawling becomes excessive, the load may be dropped orotherwise uncontrollably discharged, thus creating hazards to theoperator.

The apparatus of the present invention includes a pair of adjustablypositioned sling means which may be utilized to handle or otherwisesupport heavy loads, and to turn these loads with a reduced risk ofhaving the belt move axially on the rotating support drum and therebyinadvertently discharge the load. Specifically, a pair of axially spaceddrums are provided, with the drums being controllably rotated bysuitable power means. Each drum carries a suspension sling in the formof a loop extending or passing over the surface of the drum, with thesling being adjustable in length to accommodate varying size loads andparticularly adapted to reduce the tendency to crawl or otherwise movealong the axis of the drum. In addition, means are provided for ease ofmaintenance of the apparatus, including in particular, means for readilyremoving slings from the drums.

SUMMARY OF THE INVENTION Therefore, it is a primary object of thepresent invention to provide an improved load supporting and turningsling means for handling heavy loads, wherein the gap distance betweenthe individual slings is readily adjustable to accommodate a variety ofload sizes.

It is yet a further object of the present invention to provide animproved load supporting and turning sling means for handling heavyloads such as stone or the like which is arranged to accommodateirregularly shaped articles, such as articles having a configuration ofother than a rectangular parallelepipedon.

It is still a further object of the present invention to provide animproved load supporting and turning sling means for handling heavyloads which is provided with a pair of endless loop slings which arearranged in captive relationship over a pair of axially spaced drums,

and wherein the axial disposition of the slings may be readily adjustedin order to accommodate loads with varying dimensions.

It is still a further object of the present invention to provide animproved load supporting and turning sling means for handling heavyloads which is provided with a pair of axially spaced and coaxiallyarranged drum means, with each drum having an endless loop slingarranged thereover, and with the sling having a crosssectional thicknesswhich is small in relation to the diameter of the drum in order toimprove the load handling capability of the sling.

Other and further objects of the present invention will become apparentto those skilled in the art upon a study of the following specification,appended claims, and accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a front elevational view ofthe improved load supporting and turning apparatus of the presentinvention, and illustrating the endless loop webs in partially brokenaway form;

FIG. 2 is a vertical sectional view taken along the line and in thedirection of the arrows 2-2 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT In accordance with the preferredembodiment of the present invention, and with particular reference toFIG. 1 of the drawing, the load supporting and turning apparatusgenerally designated 10 includes a frame means with a primary centralsupport beam 11 having a plurality of brackets 12, 13, 14 and 15depending therefrom. Brackets 12-15 inclusive are secured by welding orother conventional means to beam 11. As is indicated in FIG. 1, eyes 17and 18 are also coupled to beam 11, in order to appropriately suspendthe apparatus from an overhead support.

A drive shaft generally designated 20 is journaled for rotation withinthe individual brackets 12-15 inclusive, the drive shaft 20 beingoperatively coupled to the output of transmission or control 21, withthe main power being supplied to transmission 21 by motor 22. Stubshafts 23 and 24 extend outwardly from transmission housing 21, thesestub shafts 23 and 24 collectively forming a central shaft segment forthe drive shaft means. Stub shafts 23 and 24 are coupled to the outershaft segments 25 and 26 by means of a double sprocket chain couplingarrangement such as is shown at 27 and 28 respectively. The purpose ofthe coupling, while described more fully hereinafter, permits readydisassembly of the drive shaft segments to facilitate a change ofslings.

Journal bearings are provided as at 30, 31, 32, and 33 for supportingthe drive shaft within the individual brackets 112-15 inclusive. Thesebearings are preferably secured to the individual brackets by means ofthrubolts, such as is illustrated at 35, for example. It is the bolts35-35 which support the shaft within the individual brackets, with theindividual bearing structures 30-33 inclusive being utilized to maintainproper axial alignment with the various portions of the drive shaft.

As has been indicated, drum means are secured to the outer drive shaftsegments, with the drum means including an outer sleeve portion such asthe sleeves 40 and 41, with end caps 42 and 43 being coupled to sleeve40, and caps 44 and 45 being coupled to sleeve 41. The individual endcaps have a central bore extending therethrough in order to accommodatethe shaft segments, as is apparent in the drawing. Thus, controlledrotation of the individual drums is accomplished by motor 22 which is,of course, reversible, with the torque from the motor being directed tothe shaft 20 through the transmission 21. Torque arm 47 is coupledbetween transmission 21 and frame element 11, as is indicated in thedrawing. Also, control box 48 is provided in order to house theappropriate circuitry for controlling the output of motor 22.

A pair of endless loop slings 50 and 51 are provided, with these slingshaving a cross-sectional thickness dimension which is'small relative tothe diameter of the drum. The slings 50 and 51 are arranged in captiverelationship over'the drums and are arranged to be disposed inpre-selected disposition along the drums, as is indicated in FIG. 1. Formost purposes, the crosssectional thickness of the loop slings should beless than about percent of the diameter of the drum over which it isrunning. Such a relationship minimizes the tendency of the belt to crawlor walk along the surface of the drum when irregularly shaped loads arebeing handled.

One belt system which has been found particularly adapted for use withhandling heavy loads is a belt prepared from two individual sections ormembers, a first section or member being reinforced with nylon, with thesecond member also utilizing a nylon web reinforcement which isimpregnated with polyvinyl chloride. Polyvinyl chloride is normallyresistant to abrasion, and provides a frictional surface for contactingthe outer periphery of drums 40 and 41. As is apparent, the heavilyreinforced section or member is provided for the purpose of withstandingthe heavy loads to be imposed.

As is apparent in the drawing, the various segments of drive shaft 20are arranged in coaxial relationship, one to another. It will beapparent that the outer seg ments of shaft 20 must be axially aligned,however the central segment may be arranged in axial parallelrelationship, if desired, with appropriate coupling means being utilizedto transfer the rotational energy from the central shaft portion to theouter shaft portions.

As is apparent in the drawing, the sleeve members 40 and 41 which formthe individual drums are generally elongated, and have a substantiallyequal length, one compared to the other. Also, for purposes of effectiveutilization of the structure, the length of the sleeves 40 and 41 willgenerally be substantially equal to the distance separating the innerends of these drums.

in order to accommodate a change in slings, the operator is simplyrequired to remove support bolts 35-35 from the appropriate brackets,and following de-coupling of the double sprocket chain coupling, thedrum structure may be removed from the assembly, and the sling replaced.Such an operation is expedient in view of the slotted portions or areas53 formed in the individual brackets 12-15 inclusive.

With attention being directed to FIG. 2 of the drawing, the individualcomponents of the sling members are illustrated, with the heavilyreinforced segment being shown at 55, and the frictional segment beingshown at 56. This compound sling has been found to be both durable andreliable in use.

As has been indicated, the cross-sectional thickness of the endless loopslings is small relative to the diameter of the load supporting sleeveover which the sling moves. In a typical stone turning structure, thesleeves 40 and 41 had an outer diameter of 9 inches, with theappropriate webbing having a cross-sectional thickness of approximatelynine-sixteenths inch. Such an arrangement permitted the carrying ofheavy loads without excessive crawling of the webbing on the drum whenirregularly shaped loads were being handled.

I claim:

1. Load turning sling means for handling heavy loads comprising:

a. frame means including a central support beam and a plurality ofbrackets secured in depending relationship from said beam;

b. drive shaft means journaled for rotation within said brackets andhaving a central shaft segment and a pair of coaxially disposed outersegments arranged in axial alignment with said central segment anddetachably secured to said central segment, the inner and outer ends ofsaid outer segments each being held in depending relationship from saidbeam by one of said brackets;

. c. drive means for controllably rotating said drive shaft means;

d. drum means with an elongated axial dimension secured to said outersegments and having an outer sling receiving drive surface thereon and apair of enlarged sling retaining heads at each end thereof;

e. a pair of endless loop slings each having a generally rectangularcross-section and each having a crosssectional thickness dimension whichis small relative to the diameter of said drum arranged in captiverelationship, one over each of said drums, and between adjacent pairs ofsaid brackets.

2. The load turning sling means as defined in claim 1 being particularlycharacterized in that each of said endless loop slings has reinforcingfibers maintained therewithin, with a coating on the inner surface ofsaid sling for providing frictional engagement between said sling andsaid drive surface.

3. The load turning sling means as defined in claim 1 being particularlycharacterized in that said drive shaft means are arranged coaxially, oneto another.

4. The load turning sling means as defined in claim 1 being particularlycharacterized in that said drum means are of substantially equal length,and are spaced apart by a distance substantially equal to the drumlength.

5. The load turning sling means as defined in claim 1 being particularlycharacterized in that said depending brackets are slotted foraccommodating ready decoupling of said drum means.

6. The load turning sling means as defined in claim 1 being particularlycharacterized in that the crosssectional thickness dimension of saidloop slings is less than l0 percent of the diameter of said drum means.

7. The load turning sling means as defined in claim 1 being particularlycharacterized in that said endless loop slings are formed with an innerring member and an outer ring member, with said inner ring member havinga frictional surface for engaging said drum means, and with said outerring member having a plurality of nylon reinforcing fibers forming theassembly. a

1. Load turning sling means for handling heavy loads comprising: a.frame means including a central support beam and a plurality of bracketssecured in depending relationship from said beam; b. drive shaft meansjournaled for rotation within said brackets and having a central shaftsegment and a pair of coaxially disposed outer segments arranged inaxial alignment with said central segment and detachably secured to saidcentral segment, the inner and outer ends of said outer segments eachbeing held in depending relationship from said beam by one of saidbrackets; c. drive means for controllably rotating said drive shaftmeans; d. drum means with an elongated axial dimension secured to saidouter segments and having an outer sling receiving drive surface thereonand a pair of enlarged sling retaining heads at each end thereof; e. apair of endless loop slings each having a generally rectangularcross-section and each having a cross-sectional thickness dimensionwhich is small relative to the diameter of said drum arranged in captiverelationship, one over each of said drums, and between adjacent pairs ofsaid brackets.
 2. The load turning sling means as defined in claim 1being particularly characterized in that each of said endless loopslings has reinforcing fibers maintained therewithin, with a coating onthe inner surface of said sling for providing frictional engagementbetween said sling and said drive surface.
 3. The load turning slingmeans as defined in claim 1 being particularly characterized in thatsaid drive shaft means are arranged coaxially, one to another.
 4. Theload turning sling means as defined in claim 1 being particularlycharacterized in that said drum means are of substantially equal length,and are spaced apart by a distance substantially equal to the drumlength.
 5. The load turning sling means as defined in claim 1 beingparticularly characterized in that said depending brackets are slottedfor accommodating ready de-coupling of said drum means.
 6. The loadturning sling means as defined in claim 1 being particularlycharacterized in that the cross-sectional thickness dimension of saidloop slings is less than 10 percent of the diameter of said drum means.7. The load turning sling means as defined in claim 1 being particularlycharacterized in that said endless loop slings are formed with an innerring member and an outer ring member, with said inner ring member havinga frictional surface for engaging said drum means, and with said outerring member having a plurality of nylon reinforcing fibers forming theassembly.